A vehicle tire typically comprises a radial carcass, tread, and tread reinforcing breaker or belt disposed between the carcass and tread. The breaker component pursuant to conventional techniques is constructed across the tread region as either a single sheet component applied unitarily or a series of overlapping strips extending in the peripheral direction of the tire. The width of the overlap between adjacent strips may be selected across the width of the tire to alter the characteristics of the breaker or to adjust the overlapping breaker strips so that the cumulative width of the strips covers the width of the target breaker region beneath the tread. Variations in the width of the tire may require strips of differing widths or the overlapping of such strips to a greater or lesser extent. U.S. Pat. No. 5,213,642 is representative of such an approach.
While working well and finding commercial application, the technique of constructing a breaker onto a carcass by the overlapping application of breaker strips one at a time carries significant disadvantages. The overlapping portions of adjacent breaker strips represents increased and often unnecessary material waste, adding to the cost of manufacture. Moreover, it is preferable that the breaker layer comprise a single layer applied as non-overlapped strips in order to enhance uniformity and the consistency of tire construction across the tire radial width. However, merely applying strips such as those proposed in U.S. Pat. No. 5,213,642 edge to edge across the tread region rather than an overlapping construct causes a new set of difficulties and can result in material waste as well. For example, a typical passenger tire may require 20 to 60 strips. Applying the strips at an angle in an edge to edge, zero clearance, configuration would require cutting a 21st or 61st strip to fill a final gap. Destruction of a breaker strip in order to fill a remainder gap on each tire results in an unacceptable level of scrap and high resultant cost of manufacture.
Alternatively, strips of a precise and prescribed width could be utilized to exactly cover the target region in an edge to edge non-overlapping layer in order to leave no remainder gap. While theoretically possible, such an approach would necessitate expensive production and inventorying of strips of varying widths in order to accommodate tires of varying sizes. Not only would the cost of inventory and production equipment escalate, but the change-over time required to transition strips of one width out and strips of a second width in for tires of varying sizes would undesirably complicate the manufacturing process and add cost to the each tire.
Accordingly, there remains a need for a manufacturing process and breaker construction that would accomplish the construction of a breaker onto a tire carcass in a non-overlapped configuration on a carcass one strip at a time. Such a process should eliminate or reduce to an acceptable level the remainder gap at the conclusion of the breaker formation. Additionally, the procedure and method should reduce equipment cost and equipment footprint, thus reducing floor space costs and manpower. The process should reduce change over time from one setup to another and allow belts to be produced for tires of varying sizes without necessitating individual component rolls of strips of varying width, angle, and gage.